DESCRIPTION (taken directly from the application) The gastric response to Helicobacter pylori (Hp) differs between children and adults. In children, gastritis is the most common manifestation whereas peptic ulcers are uncommon. The issues of whether Hp gastritis induces recurrent abdominal pain and requires treatment remain current controversies in pediatric gastroenterology. Prior studies on treatment outcomes in pediatric II. pylori gastritis have had three limitations: symptomatic responses have been evaluated only at a single short-term point 4 to 8 weeks after initiation of therapy, quality of life indicators relevant to children have not been measured, and the contribution of psychological variables has not been assessed. To address these limitations and provide a more rigorous study of therapeutic responses to Hp eradication, we propose to: 1) develop a computerized outcomes telemonitoring system to assess both GI symptoms (e.g. intensity and duration of pain) and quality of life (e.g. school attendance) for 2 years; 2) compare with effects of clinical outcomes of triple eradication therapy for H. pylori with that of gastritis treatment alone; 3) relate the temporal response to treatment to three indirect markers of gastric recovery including bacterial eradication (13C-urea breath test), gastric inflammation (serum pepsinogen I), and gastrin secretion (plasma gastrin, gastrin-releasing peptide, somatostatin); and 4) determine if psychological factors and medical non-compliance influence treatment outcomes. This novel computerized outcomes methodology will enable us to prospectively and continuously (twice weekly) assess both short and long- term treatment response by administering a pre-recorded questionnaire over a telephone modem; the subject's response entered by telephone keypad will be directly transferred into our database. If validated, this automated outcomes assessment tool could be used in multi-center trials in pediatric Hp gastritis to study the relative efficacy of various therapeutic regimens, or, to study other GI disorders in which either the relationship between pathologic finding and symptomatology is in question.